四川蛇纹石猫眼的地质特征及显微结构分析

蛇纹石猫眼是一种具有猫眼效应的罕见玉石品种。本文主要探讨了蛇纹石猫眼的地质特征,采用光学显微镜对产于四川石棉县的蛇纹石猫眼样品进行了显微结构分析。结果表明:四川蛇纹石猫眼的组成矿物蛇纹石的形态主要有微纤维状和鳞片状。岩石的显微结构主要有微纤维变晶结构、微鳞片变晶结构、交代假象结构和网格状结构,并以前者为主,约占30%。微纤维变晶结构是蛇纹石猫眼形成的主要原因。交代假象结构主要表现为蛇纹石对早期矿物橄榄石和辉石的交代而表现出橄榄石和辉石的假象。交代假象结构和网格状结构的存在证明了蛇纹石猫眼的岩石成因为超基性岩石的蛇纹石化作用。     

Distribution and Collection of China’s Dinosaurs

<正>It is estimated that the world has discovered more than1000 species and 800 genera of dinosaurs.Chinese scientists have named more than 170 species of dinosaurs,with 17 genera and 44 species of dinosaur egg fossils,35genera and 39 species of dinosaur footprints,since their first discovery in China in 1902.China has dinosaur occurrences from the Upper Triassic to the Upper     

中国天山山区降水空间分布模拟及成因分析

为了研究中国天山山区降水空间分布规律及其形成机理,基于研究区DEM及气象站点数据资料,运用偏最小二乘法和GIS技术建立了山区降水估算模型,并分析其降水成因。结果表明:天山山区年降水具有明显的经度和纬度地带性,西段多于东段,北坡(迎风坡)多于南坡(背风坡);研究区降水在海拔4 000 m以下呈线性增加特征,随后显著减少,在5 500 m左右出现第二极大值带;坡度小于50°时降水与坡度呈显著正相关。在地形抬升条件下,随气温下降和相对湿度上升使降水增加,这也是山区降水形成的必要条件。总体来看,偏最小二乘法可以有效解决降水及各因子间多重相关性问题,模型回归效果较显著,在模拟山区降水方面具有一定适用性。     

自贡大山铺恐龙动物群埋藏环境及集中埋藏原因分析

四川自贡大山铺以其集中埋藏数量众多的恐龙化石而闻名于世,恐龙化石集中埋藏的原因一直是人们关注的焦点问题之一.笔者在对自贡恐龙博物馆内及其附近地层剖面调查的基础上,根据对该处埋藏恐龙化石地层的岩相、沉积构造、砂体形态特征以及沉积背景的分析,认为恐龙化石的埋藏环境为湖泊三角洲,恐龙由于某种原因死亡后,经过河流搬运埋藏于湖泊三角洲前缘的河口砂坝之中,而非由于中毒异常死亡原地埋藏.     

Pumas as taphonomic agents: A comparative analysis of actualistic studies in the Neotropics

Puma (Puma concolor) taphonomic action on vertebrate assemblages in the Neotropics is described and analyzed. Actualistic information based on the literature and observations are presented from a comparative perspective, to determine some general patterns and, particularly, the ranges of variation in this felid's action. Information available for the Nearctic region is considered for comparative purposes. Particular attention is given to cases departing from the more general trends, such as one case in Mendoza (Argentina) in which the intensity of bone damage is outstanding. Variation in puma taphonomic action in the Neotropics is increasingly apparent as new studies are carried out, and knowledge on the range of this variation and the conditions under which it occurs needs to be deepened by future research.     

Long-term variations of caloric insolation resulting from the earth's orbital elements

A contribution to a global a priori model of climatic changes for the Quaternary Ice Age is tentatively proposed. Special emphases are put on the astronomical problem and on the insolation available in the assumption of a perfectly transparent atmosphere. It is shown that for these two steps an accurate solution can be obtained, limiting the cumulative effect of computational approximation and allowing input to a climatological model to be of real value. For the earth's orbital elements, the proposed solution includes terms dependent to the second degree on disturbing masses, to third degree on planetary eccentricities and inclinations and, for the obliquity and the annual general precession in longitude, also to the second degree on earth's eccentricity. Improvements introduced by this solution upon the insolation computed through the Milankovitch series are deduced from the differences between Vernekar's results and present ones. The relative agreement between results clearly shows that the new astronomical solution is probably close to the ideal one from a paleoclimatological point of view.     

Benthic foraminifera in a deep-sea high-energy environment: the Moira Mounds (Porcupine Seabight,SW of Ireland)

Cold-water coral ecosystems represent unique and exceptionally diverse environments in the deep-sea. They are well developed along the Irish margin, varying broadly in shape and size. The Moira Mounds, numerous small-sized mounds, are nestled in the Belgica Mound Province (Porcupine Seabight, North-East Atlantic). The investigation of living (Rose Bengal stained) and dead benthic foraminiferal assemblages from these mounds allowed to describe their distribution patterns and to evaluate their response to environmental variability. Quantitative data was statistically treated to define groups of species/genera associated to specific habitats. The Moira Mounds differ from their larger neighbours by the reduced spatial variability of benthic foraminiferal assemblages, living assemblages only distinguishing coral-rich and coral-barren areas. The ecological needs of corals are highlighted by the abundance of Alabaminella weddellensis and Nonionella iridea, phytodetritus-feeding species in coral supporting sediments. Living foraminifera in sediments from the Moira Mounds concentrate in the upper first centimetre. Infaunal species may be affected by bioturbation and/or reworking by the strong currents in the area. Dead foraminiferal assemblages from the Moira Mounds resemble those described for the sandwave facies in adjacent giant mounds, suggesting similar processes in facies deposition.     

剥蚀-沉积体系中剥蚀量与沉积通量的定量对比研究——以岷江流域为例

岷江流域与成都盆地之间是以岷江为联结的剥蚀-沉积体系。根据成都盆地已有的钻孔资料和原始数据,用Sufer软件制作成都盆地晚新生代等厚图,利用等厚线计算了成都盆地残留的沉积通量,并通过成都盆地的地质演化再造恢复了成都盆地潜在的沉积通量,结果表明,成都盆地潜在的沉积通量为1665km3。同时,采用了输沙量、宇宙核素、数字高程模型、河流下切速率和裂变径迹等方法分别计算了岷江上游流域的剥蚀速率、剥蚀厚度和剥蚀量,结果表明,岷江流域的剥蚀速率应介于0.26~0.5mm/a之间,剥蚀厚度介于0.94~1.44km之间,剥蚀量介于21213.50~32636.16km3之间。在此基础上,我们对成都盆地沉积通量与岷江流域的剥蚀量进行了对比分析,结果表明,在岷江上游流域与成都盆地之间的剥蚀—沉积体系中,成都盆地沉积通量与岷江流域的剥蚀量之间的比率介于5.11%~7.85%之间,成都盆地沉积通量与岷江流域剥蚀量不相匹配,成都盆地属于半封闭盆地,因此,不能利用成都盆地晚新生代以来沉积物充填体积恢复岷江上游流域的剥蚀速率、剥蚀厚度和剥蚀量。     

灿烂辉煌的冰雪人生——读谢自楚先生博客有感

<正>每当我读老谢写的回忆录,总有一种亲切而又震撼心灵的感觉.尤其是最近读到他在新浪博客上发表的"谢自楚的冰雪人生"(http://blog.sina.com.cn/s/blog_c41f196f0102uyks.html),作为同龄人和长期共事的战友,我感慨万分.谢自楚是我们这一代冰雪研究者唯一一位科班出身的学者.他牢记中国、原苏联两国师长们的教导,牢记少年时期的誓言,尽其终生为我国冰雪科     

Catchment contrasts: Comparing young people’s experiences and knowledge of a river environment

Early geographies focussed on children have recorded their environmental and spatial perceptions. Contemporary theoretical and methodological advances in, and beyond, children’s geographies have supported a more complex engagement with environmental topics. Complementing this work, a study of young people’s experience and knowledge of a river in southern New Zealand is presented. Data were gathered from four contrasting locations within one, 5650 sq. km, catchment, employing child-oriented, multi-method approaches. Data analysis confirms existing literature highlighting how young people are competent knowledge producers with varying experiences and understandings. Some of this variation can be appreciated by focussing on factors of age, gender and catchment location. Together these findings are relevant to both academic and planning circles and implications for young people’s participation in catchment management are noted as a key area for further development of work of this kind.     

Stable lead isotope ratios and metals in freshwater mussels from a uranium mining environment in Australia’s wet-dry tropics

Concentrations of Fe, Mn, Cu, Zn, U and Pb, and stable Pb isotopes ²⁰⁶Pb, ²⁰⁷Pb and ²⁰⁸Pb were measured via inductively coupled plasma mass spectrometry in sediments, water and freshwater mussels (Velesunio angasi) from two catchments in the Alligator Rivers Region, Australia. Sediment U and Pb concentrations were higher in Magela Creek downstream than upstream of the Ranger U mine due to the mineralised nature of the catchment and potential local input of sediment from the mine site. Water metal concentrations were highest in Georgetown Creek, which is a tributary of Magela Creek and part drains the Ranger mine site, but there was little difference in concentrations between the Magela Creek upstream and downstream sites. Metal concentrations in mussels collected immediately upstream and downstream of the mine site also showed little difference, whereas Pb isotope ratios displayed a very distinct pattern. The ²⁰⁶Pb/²⁰⁷Pb and ²⁰⁸Pb/²⁰⁷Pb isotope ratios were more uranogenic downstream than upstream of the site and also more uranogenic than ratios measured in Sandy Billabong, a reference billabong in a catchment not influenced by U mineralisation. Isotope ratios were also more uranogenic in younger mussels, potentially due to the increasing footprint of the mine site over the past decade. The most uranogenic ratios were found in mussels from Georgetown Creek and at a site approximately 2 km downstream. At Mudginberri Billabong, approximately 12 km downstream of the Ranger mine, the relative contribution of uranogenic Pb to the total Pb concentration in mussels was small and overwhelmed by the input of industrial Pb with a Broken Hill type Pb signature. Whereas metal uptake by and thus concentrations in mussel flesh are influenced by water chemistry, mussel condition and metabolic rates, Pb isotope ratios are independent of these factors and provide a powerful means of source apportionment of contaminants in mussels and waterways, in particular in an U mining environment.     

山东省沂沭河干流水环境质量评价与趋势分析

根据多年水质监测资料，对沂沭河干流水环境质量进行综合评价；采用Kendall季节检验趋势分析法，对沂沭河水系水环境质量变化趋势进行了探讨，为治理改善沂沭河水环境质量提供科学依据。     

Lithium Resources in Brine of China’s Sea Salt Field Operations

正Objective With the rapid development of mobile power and electronic vehicles,the application of lithium is in the ascendant,and the contradiction between its supply and demand is prominent.     

广西大厂碳酸盐型硫化物尾矿中镉的地球化学行为

采用改进欧共体参比司法(BCR)提取广西大厂锡-多金属矿区巴里尾矿库的碳酸盐型尾矿的Cd。研究表明,氧化作用使原尾矿中磁黄铁矿、方铅矿、方解石被大量消耗,在产生酸水的同时释放出大量重金属;该尾矿的表层形成厚层的次生石膏和纤铁矿胶结的硬层,可富集释放出来的Cd;在氧化层中Cd主要以酸提取态形式赋存,其潜在迁移性最强,很容易进入环境,带来严重的镉污染。